In chronic spontaneous urticaria, high numbers of dermal endothelial cells, but not mast cells, are linked to recurrent angio-oedema.

BACKGROUND: Chronic spontaneous urticaria (CSU) is an inflammatory skin disorder characterized by recurrent weals, angio-oedema or both. Recent studies have shown that the number of endothelial cells is increased in the skin of patients with CSU, but the underlying mechanisms and clinical implications of this are unclear. AIM: To evaluate whether mast cell (MC) or endothelial cell (EC) numbers correlate with CSU and whether they are relevant for disease duration, disease activity or the presence of clinical features. METHODS: We determined the numbers of CD31+ ECs and MCs in nonlesional skin of 30 patients with CSU using quantitative histomorphometry, and assessed their correlation with each other and with clinical features such as disease duration, disease activity and occurrence of angio-oedema. RESULTS: The numbers of MCs and ECs were high in the nonlesional skin of patients with CSU, but did not correlate with each other. Neither MC number nor EC number correlated with disease duration or disease activity. Interestingly, patients with high numbers of cutaneous CD31+ ECs had higher rates of recurrent angio-oedema and vice versa. CONCLUSIONS: Based on these findings, we speculate that vascular remodelling and MC hyperplasia in patients with CSU occurs independently and via different mechanisms. Targeting of the mechanisms that drive neoangiogenesis in CSU may result in novel therapeutic strategies for the management of patients with angio-oedema.

Tumor vascularization and clinicopathologic parameters as prognostic factors in merkel cell carcinoma.

PURPOSE: Merkel cell carcinoma (MCC) is a rare but aggressive neuroendocrine tumor of the skin with an increasing incidence. The clinical course is variable and reliable prognostic factors are scarce. Tumor angiogenesis has been shown to have prognostic impact in different types of cancer. The aim of our study was to determine potential prognostic factors, including tumor vascularization, for clinical outcome of MCC. METHODS: The medical records of 46 patients with MCC diagnosed between 1997 and 2010 were analyzed retrospectively. Tissue samples were immune-stained for the lymphatic endothelial vessel marker podoplanin/D2-40 and the panvascular marker CD31. These immunostained sections were analyzed using computer-assisted morphometric image analyses. Aside from the parameters of tumor vascularization, clinicopathologic features were investigated, and progression-free survival (PFS) and tumor-specific survival (TSS) were assessed. Univariate and multivariate analyses were performed to determine prognostic factors. RESULTS: Male sex of the MCC patients and a high cross-sectional whole vessel area (WVA) in relation to the entire tumor area as determined on CD31-stained tumor sections were found to be negative prognostic factors for PFS in a univariate and multivariate regression analysis. Ulceration of the primary tumor was significantly associated with both impaired PFS and TSS. CONCLUSIONS: Our results indicate a high prognostic impact of tumor vascularization on the clinical outcome of MCC patients. Male sex and ulceration of the primary MCC were identified as independent unfavorable prognostic markers for the clinical outcome. As an outlook, MCC patients with increased angiogenesis might be identified and subjected to a targeted anti-angiogenic treatment.

Allergen-loaded strontium-doped hydroxyapatite spheres improve allergen-specific immunotherapy in mice.

BACKGROUND: Immunomodulatory interventions play a key role in the treatment of infections and cancer as well as allergic diseases. Adjuvants such as micro- and nanoparticles are often added to immunomodulatory therapies to enhance the triggered immune response. Here, we report the immunological assessment of novel and economically manufactured microparticle adjuvants, namely strontium-doped hydroxyapatite porous spheres (SHAS), which we suggest for the use as adjuvant and carrier in allergen-specific immunotherapy (ASIT). METHODS AND RESULTS: Scanning electron microscopy revealed that the synthesis procedure developed for the production of SHAS results in a highly homogeneous population of spheres. Strontium-doped hydroxyapatite porous spheres bound and released proteins such as ovalbumin (OVA) or the major cat allergen Fel d 1. SHAS-OVA were taken up by human monocyte-derived dendritic cells (mdDCs) and murine DCs and did not have any necrotic or apoptotic effects even at high densities. In a murine model of ASIT for allergic asthmatic inflammation, we found that OVA released from subcutaneously injected SHAS-OVA led to a sustained stimulation of both CD4+ and CD8+ T cells. Allergen-specific immunotherapy with SHAS-OVA as compared to soluble OVA resulted in similar humoral responses but in a higher efficacy as assessed by symptom scoring. CONCLUSION: We conclude that SHAS may constitute a suitable carrier and adjuvant for ASIT with great potential due to its unique protein-binding properties.

Sentinel lymph node biopsy and risk factors for predicting metastasis in cutaneous squamous cell carcinoma.

BACKGROUND: Cutaneous squamous cell carcinoma (cSCC) is a common cancer capable of metastasis. Sentinel lymph node biopsy (SLNB) may be a valuable adjunct for patients with cSCC at high risk for metastasis. However, data on risk factors for metastasis and results of SLNB from patients with cSCC are limited. OBJECTIVES: To evaluate risk factors for metastasis in patients with cSCC in a large cohort study with long-term follow-up and to determine the value of SLNB. METHODS: We retrospectively analysed all records of patients who underwent excision of cSCC between January 2005 and August 2009 at a tertiary referral centre. In total, 143 patients were included in the cohort, including 17 patients with SLNB and a follow-up time of ≥ 24 months. RESULTS: Tumour thickness > 4 mm and recurrent cSCC were strongly associated with metastatic disease. All metastases in this cohort occurred within 24 months of follow-up. SLNB showed a low sensitivity with regard to the development of metastasis. Six of 17 patients developed metastatic disease despite a negative SLNB. CONCLUSIONS: Patients with risk factors (cSCC with a tumour thickness > 4 mm or recurrent disease) may develop metastases within the first 2 years despite a negative SLNB. Therefore these patients should be closely monitored during the follow-up. Based on our data SLNB does not provide diagnostic value for patients with cSCC.

Long-term outcome of intravenous therapy with rituximab in patients with primary cutaneous B-cell lymphomas.

BACKGROUND: The monoclonal antibody rituximab directed against the B-cell antigen CD20 was approved for the treatment of B-cell lymphomas and maintenance therapy in follicular lymphomas more than a decade ago. However, median follow-up in case series of intravenous rituximab therapy in primary cutaneous B-cell lymphomas (CBCL) lasts only up to 3 years. We retrospectively analysed a cohort of CBCL patients treated with rituximab to gain more long term information. PATIENTS AND METHODS: Eighteen patients, treated intravenously with rituximab for a primary cutaneous B-cell lymphoma [follicle centre lymphoma (PCFCL), n = 11; diffuse large B-cell lymphoma, leg type (PCLBCL, leg type), n = 5; marginal zone B-cell lymphoma (PCMZL), n = 2] were included. The response rate (RR), time to relapse (TTR), and course of the disease after treatment were analysed. RESULTS: The overall RR was 89% (16 of 18 patients). Within the median follow-up time of 52 months, 81% (13 of 16) of patients experienced a relapse; the median TTR was 25 months. The duration of remission was significantly shorter in patients presenting with generalized skin lesions at start of therapy. Both nonresponding patients suffered from PCLBCL, leg type, with extracutaneous manifestations. In responders severe adverse events, the occurrence of extracutaneous dissemination or nodal lymphomas were not observed during follow-up. CONCLUSIONS: Therapy with rituximab is effective and safe for the treatment of PCFCL, but relapses, in particular in patients with generalized skin involvement, are commonly observed. However, all patients with relapses responded well to treatment and therefore maintenance therapy does not seem to be indicated. Patients with PCLBCL, leg type, should receive chemotherapy in addition to rituximab.

Evaluation of different methods in the follow-up of patients with indolent types of primary cutaneous lymphomas.

BACKGROUND: Primary cutaneous lymphomas (CLs) are a heterogeneous group of diseases arising from B or T lymphocytes. CLs are grouped according to their clinical behaviour into indolent, intermediate and aggressive types. Indolent CLs respond well to therapy but frequently relapse, resulting in prolonged periods of follow-up. OBJECTIVES: To evaluate the outcome of follow-up examinations in indolent CL. METHODS: We retrospectively analysed a cohort from a CL outpatient clinic at a tertiary referral centre. Seventy-five patients with indolent cutaneous T-cell lymphomas (CTCLs) and 34 patients with indolent cutaneous B-cell lymphomas (CBCLs) were included. The value of clinical examination, blood tests and imaging procedures for detection of recurrence or progression was assessed. RESULTS: In patients with CTCL all but one disease recurrences were detected by clinical examination. Lymph node or organ involvement was detected by imaging procedures in seven patients, of whom all but one had recurrent or persistent CL lesions. In CBCL all recurrences were detected by clinical examination. CONCLUSIONS: Patients with indolent CL confined to the skin should be followed primarily by clinical examination. However, in patients who are refractory to treatment regular screening of lymph nodes by ultrasound may enable earlier detection of disease recurrence or progression.

Distribution of bacteria in the epidermal layers and hair follicles of the human skin.

Previous studies over recent years have revealed the presence of a resident bacterial population in the human skin throughout the entire body. However, the localization and composition of the bacteria within the epidermis and the skin appendages have not been fully investigated. Using differential tape stripping, cyanoacrylate skin surface biopsies and mapping of hair follicles, bacteria on the forearms of study participants were isolated, mapped, cultured and identified with respect to their origin within the epidermis and the hair follicles. Our studies showed that 85% of the bacteria were found within the first 6 corneocyte layers and roughly 25% of the cutaneous bacterial population were localized within the hair follicles. The microbial flora of the skin between individuals is subject to considerable fluctuations. Micrococcaceae represent the biggest fraction of hair-follicle-associated bacteria. The techniques developed for this study allowed us to selectively investigate the bacterial population within the hair follicles. Our results point out the role of skin appendages as potential microbial reservoirs and the need to develop new antiseptic formulations that sufficiently penetrate into the hair follicles.

Prevention of non-melanoma skin cancer in organ transplant patients by regular use of a sunscreen: a 24 months, prospective, case-control study.

BACKGROUND: Skin cancers represent a major challenge within the ever growing group of long time surviving organ transplant recipients (OTR) world wide. Especially UV-induced non-melanoma skin cancers (NMSC) like invasive squamous cell carcinomas (SCC) and actinic keratoses (AK), and basal cell carcinoma (BCC), outnumber every other form of cancer in organ transplant recipients. Despite encouraging reports of protective effects of broad-spectrum sunscreens in immunocompetent patients, evidence for the prevention of NMSC in immunocompromised patients is still missing. OBJECTIVES: To assess preventive effects of regular sun-screen use on AK, SCC and BCC in chronically immunocompromised organ transplant recipients. METHODS: Hundred and twenty matched (age, sex, skin type, graft, transplant duration, previous post-transplant skin malignancies) organ transplant recipients (40 heart, 40 kidney, 40 liver grafted) were recruited for this prospective, single-center study. Both groups received equally written and oral information on sun protection measures. Sixty patients were provided with a free broad spectrum study-sunscreen (SPF>50, high-UVA absorption) for daily application of 2 mg cm(-2) to the head, neck, forearms, and hands. RESULTS: All 120 patients completed the 24 months study. Within this 24 month study interval 42 of the 120 patients developed 82 new AK (-102 sunscreen group vs. +82 control; P<0.01), 8 new invasive SCC (0 vs. 8; P<0.01) and 11 BCC (2 vs. 9; ns). In spite of equal numbers of AK at baseline, a marked difference in favor of the intent-to-treat sunscreen group was recorded after 24 months (89 vs. 273; P<0.01, mean difference 3.07 [1.76-4.36]) and the lesion count was significantly lower as compared to the initial visit (89 vs. 191; P<0.01, mean difference 1.7 [0.68-2.72]). With an average of 5.6 applications per week throughout the 24 months the study sunscreen was generally well tolerated. Serum 25-hydroxy vitamin D levels as marker for vitamin D status were decreased in all patients without adequate substitution and 25(OH)D was found to be lower in the sunscreen-group as compared to the control group (mean value 53 ng mL(-1) vs. 60 ng mL(-1)). INTERPRETATION: Regular use of sunscreens, as part of a consequent UV-protection strategy, may prevent the development of further AK and invasive SCC and, to a lesser degree, BCC in immune-compromised organ transplant recipients.

Organ transplant recipients and skin cancer: assessment of risk factors with focus on sun exposure.

BACKGROUND: Organ transplant recipients (OTRs) have an increased risk of developing skin cancer, especially epithelial tumours. A number of factors such as immunosuppression, age, ultraviolet radiation and skin type are considered as important in aetiology. OBJECTIVES: The purpose of this study was to further evaluate the risk factors for OTRs regarding skin cancer after transplantation. A detailed investigation of the specific compounds of sun exposure was realised. METHODS: A questionnaire-based study was performed in a specialist OTR dermatology clinic from January to April 2009. The subjects were 70 organ transplanted patients who had developed some form of skin cancer after transplantation. As controls served 69 organ transplanted patients who had no history of skin cancer. The controls were matched concerning age, transplanted organ and gender. Photo protection, sun exposure and transplantation data were part of the questionnaire. Statistical analysis was performed with Mann-Whitney-U-test, chi-square test or Fisher's exact test. RESULTS: The total sun burden (TSB) and the recreational sun exposure in particular attained higher scores in the skin cancer group (TSB-score: mean 11.8 vs. 10.0, P<0.05; recreational sun exposure: mean 6.3 vs. 5.1, P<0.05). The skin cancer group had fairer skin types than the control group (median skin type 2 vs. 3, P<0.05). The OTRs who developed skin cancer have been more likely to have a history or present intake of azathioprine (mean 42% vs. 21%, P<0.05). Also, the skin cancer group has been transplanted for a longer time (mean 12.3 vs. 7.2 years, P<0.001), analogously had a younger age at transplantation (mean 49.5 vs. 52.7 years, P<0.001). CONCLUSIONS: Recreational sun exposure is of central importance for OTRs. A long period of transplantation and thus immunosuppression presents a main risk factor for the development of skin cancer in OTRs. A multi disciplinary management with the best medication and a focus on sun protection is needed to prevent skin cancer in OTRs.

Monocyte-derived dendritic cells from highly atopic individuals are not impaired in their pro-inflammatory response to toll-like receptor ligands.

BACKGROUND: Toll-like receptor (TLR) agonists are widely used as adjuvants in specific immune therapy protocols for patients with atopic disposition. Monocyte-derived dendritic cells (mDCs) are thought to be important target cells for these compounds. OBJECTIVES: To compare surface markers, TLR expression, TLR functionality after ligand stimulation, and genetic polymorphisms in the TLR 2-, 3-, and 4-genes in mDCs from atopic vs. non-atopic patients. METHODS: mDCs from highly atopic individuals (total serum IgE >1000 IU/mL) and healthy control persons (total serum IgE <75 IU/mL) were screened for TLR 1-10 expression by real-time PCR. Receptor function was analysed by IL-12 and TNF-alpha production after incubation with the respective ligands peptidoglycan (PGN) (TLR 2), polyriboinosinic-polyribocytidylic acid (poly IC) (TLR 3), lipopolysaccharide (LPS) (TLR 4), flagellin (TLR 5), and CpG-DNA/non-CpG-DNA (TLR 9). Haplotype-tagging single-nucleotide polymorphisms of the TLR 2-, 3-, and 4- genes were analysed for genetic associations. RESULTS: mDC from atopic patients showed a very similar pattern of TLR expression as controls with strong expression of TLR 2, 4, 5, 6, and 8, moderate expression of TLR 1 and 3, and no or very low expression of TLR 7, 9, and 10. After stimulation with TLR ligands, mDCs from atopic patients acquired a mature phenotype with a tendency towards a higher up-regulation of the co-stimulatory molecules CD80, CD83, and CD86 than control mDCs. IL-12 and TNF-alpha were produced at a similar level in both groups of DCs. Among the different TLR agonists, poly IC showed the strongest activation of DCs, followed by LPS, PGN, and flagellin. This was paralleled by a strong functional expression of protein kinase R and retinoid-inducible gene-I (RIG-I), two additional poly IC-sensing receptors in both groups. Genetic analysis of single-nucleotide polymorphisms in the TLR 2-, 3-, and 4-genes in both groups revealed no major allele or genotype differences. CONCLUSIONS: mDC from atopic patients are not restricted in their response to TLR-ligands. TLR agonists seem to be suitable to induce pro-inflammatory immune responses and maturation in mDCs from highly atopic individuals and represent reasonable adjuvants for specific immunotherapy reagents.